HMCJ-300kV/15kJ Lightning Impulse Voltage Generator: The Precise Choice for Insulation Testing of Medium-Voltage Equipment
In factory inspections and type tests for power transformers, circuit breakers, current transformers, insulators, bushings, and other equipment at voltage levels of 35kV and below, a precise and reliable impulse voltage generation system is essential for ensuring the accuracy of insulation performance testing. The HMCJ-300kV/15kJ Lightning Impulse Voltage Generator, launched by Wuhan Goldhome Hipot Electrical Co., Ltd., features a rated nominal voltage of 300kV, a rated energy storage capacity of 15kJ, and a three-stage Marx tower structure as its core configuration. It provides a precise, stable, and intelligent impulse insulation testing solution for various types of medium-voltage power equipment.
I. Key Features
Three-stage compact structure for efficient space utilization. The equipment adopts a three-stage tower design, with each stage rated at ±100 kV, a stage capacitance of 1.0 μF, and a total surge capacitance of 0.334 μF. The compact overall structure minimizes floor space requirements, making it particularly suitable for laboratory layouts with limited space. High-performance pulse capacitors are used for the three-phase voltage-dividing capacitors, ensuring consistency in discharge energy for every test.
Multi-waveform output with comprehensive standard coverage. The system can stably generate standard lightning impulse full-wave (1.2/50 μs), standard impulse truncated wave (2–6 μs), and user-specified non-standard impulse waves. Waveform parameters fully comply with the requirements of IEC 60060-1 and GB/T 16927 standards. When the load capacitance is 300–2000 pF, the full-wave voltage efficiency is no less than 92%, and the clipped-wave voltage efficiency is no less than 92% (no-load), ensuring the reliability and accuracy of test results.
High load capacity with stable waveform output. The generator circuit features low inductance and employs band-reject filtering measures, enabling the generation of standard surge waves even under high capacitive loads, demonstrating outstanding load capacity. The utilization coefficient for lightning surge voltage is no less than 85%, and for operational surge voltage, no less than 80%.
Constant-current charging intelligent monitoring and control system. Utilizing thyristor-based constant-current charging technology, the rated charging voltage is ±100 kV. The charging voltage can be continuously and steplessly adjusted within the range of 10% to 100% of the rated value, with a setting deviation of ≤±1% and an instability of ≤±1%. The system integrates a computer-based measurement and control platform. Through software, it can automatically capture waveforms and calculate waveform characteristic parameters in real time (such as rise time, half-peak time, and peak error), significantly reducing operational complexity and the probability of human error.
II. Operational Precautions
Pre-test Preparation. Before connecting the wires, the generator must be discharged and a grounding rod must be properly installed to ensure the safety of the personnel performing the connections. All connecting cables should be kept as short as possible. Grounding must use low-impedance connections in accordance with specifications, with a grounding resistance of less than 0.5 Ω to prevent interference.
Safety Regulations. Before energizing the equipment, all personnel must be cleared from the test area and safety warning tape must be set up. At least two people must be present during the test (one operator and one supervisor); single-person operation is strictly prohibited. After wiring is complete, the grounding rod may only be removed and power applied after the supervisor confirms safety.
Charging and Discharging. The charging voltage should be increased gradually from a low value. For the initial test, it is recommended not to exceed 50% of the rated voltage, and waveform parameters should be calibrated and adjusted first. At voltages above 70% of the rated voltage, it is recommended to charge and discharge once every 90 seconds for continuous operation; at voltages below 70% of the rated voltage, charging and discharging once every 45 seconds allows for continuous operation.
Post-Test Procedures. After the test is complete, first return the voltage regulator to zero, press the stop button, and wait until the system automatically engages the grounding rod before personnel may enter the test area. Then, use the grounding rod to discharge all capacitors step by step.
III. Introduction to Goldhome
Wuhan Goldhome Hipot Electrical Co., Ltd. was established in 2008 and is located in the Wuhan Economic and Technological Development Zone. It is a National High-Tech Enterprise and a provincial-level "Specialized, Refined, Unique, and Innovative" (SRUI) "Little Giant" enterprise. The company operates a modern factory spanning over 10,000 square meters and has specialized in the R&D and manufacturing of high-voltage testing equipment for more than two decades, holding 45 national patents and over 10 software copyrights. In 2021, it acquired the former Wuhan Sanhao Electric Co., Ltd. in full, comprehensively inheriting its over 30 years of manufacturing expertise in ultra-high-voltage oil-free testing equipment, and maintains close collaborations with research institutions such as the State Grid Electric Power Research Institute and the School of Electrical Engineering at Wuhan University. Our products strictly comply with IEC and GB standards and have been successfully exported to over 30 countries and regions, including Germany, the United States, Italy, and Vietnam. In February 2023, the HMCJ-300kV/15kJ impulse voltage generator was successfully delivered to a client in Guangdong, receiving positive market feedback. With its compact, precise, and reliable three-stage impulse voltage test system, Goldhome continues to provide a solid guarantee for the insulation reliability of medium-voltage power equipment worldwide.
